VMS/RSX tape backup problem

Hi everyone, Well, I am finally getting around to trying to recover some 26 9-track tapes I have been holding on to for at least 10 years. Some are closer to 25 years. I found out six of them had no data, and a bunch more I have been able to read and decode, including some RT-11 tapes and some VAX SIG tapes. Sorry this monologue won't make much sense to you non-DEC folks, but you might have ideas on converting from 800 to 1600 BPI anyway. Here is my dilemna. I have 6 tapes that look like they are 800 BPI, and were most likely written on an RSX-11 system. I have no 800 BPI setup, and if I did, it would be on a VAX, which may not be able to restore the savesets anyway. That is because I have a few more tapes that I can read (or at least dump) but I cannot unpack the savesets. It would appear that the tapes were written in the early days of VMS when the backup and restore utilities were really RSX-11 BCK/RST derivitives, and the current BACKUP program does not recognize the container file as a valid saveset. The label on the front of several tapes date them early 80's and talks about BCK format. The dump sort of looks like BCK stuff. The blocksize is 2064. I've had a couple of offers to try to recover the data, but I was checking to see if anybody was set up to easily read and recover the data, without a lot of reconfiguration or hassle. I'm open to suggestions. I suspect if I knew the layout of a BCK container/saveset I could unpack them myself (except for the 800 BPI stuff). Any ideas?? I also have an XXDP tape, labeled MSDP, which makes me think it is bootable. It would be nice to duplicate it, as it is not easily read to disk. The first block is 14 bytes, and the rest look like 512 bytes. And finally, I have a tape that is readable, is mountable under VMS and I can copy nearly everything off of. That is, the 400+ files up to the file that is marked HECK.BCK. That file is 2064 byte blocks, which makes me think it is also a BCK/RST format. Can't figure how I got it on the end of the tape and haven't figured out how to get it back. Cheers, Joe Heck